Many FX or Full Frame shooters see their camera being updated slowly, the regular cicle being 3-4 years. Before the D700, a majority of those were shooting on elder DX sensors (such as D2X or D200) and the change to a cleaner newer 12MP cmos FX D700 sensor was big news for them.

Nowadays the same happens again with the newer Sony exmor sensors : older D700 shooters who upgraded to a D800 or D600 are easily mesmerized by the clean files and new video options, but the truth is that an APS-C DX 16MP exmor sensor will provide the same file quality then a 24MP FX sensor in terms of noise, dynamic range and colour depth.

The real gain of FX are : bigger viewfinders and the possibility to exploit wide primes at true focal length, which is already a big plus.

The big plus of DX is : cheaper quality glass.

If there's any "biased arguments" being made here, they would be yours.

The 16MP DX sensors aren't close to the 24MP and 36MP FX sensors in terms of noise, and are only close on dynamic range is if you limit yourself to "base ISO" arguments.

DX noise is largely being hidden behind heavy-handed noise reduction that smears away detail, which may fool the defenders of DX but is pretty obvious. The 16MP exmor DX can't even match the file quality of the old D3/D700 sensor as you dial up the ISO, despite the advances in sensor tech in the interim time period. A sensor less than half as big is a big disadvantage, and always will be.